Phone unit



Feb. 25, 1930. J. s. TIIMMONS PHONE UNIT Filed Nov. ll. 1927 A Patented Feb. 25, 1930 UNITED sTATi-:s

PATENT OFFICE JOHN S. TIMMONS, F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T0 PHILADELPHIA STORAGE BATTERY COMPANY, 0F PHILADELPHIA, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA PI-INE UNIT Application led November 11, 1927. Serial No. 232,633.

modulations of. electrical current are con-V 5 verted into mechanical movements, and vice In its broad aspect, an object of my invention is to provide an electro-magnetic translating device characterized by its relatively high operating eiiiciency, by its simplicity of design and ruggedness of construction, by Iits low manufacturing cost, and by its fool proof construction. Y

`A more specific object of my invention is to provide an electro-magnetic device, that shall permit a highly concentrated magnetic field-to be established in a very small air gap, so that maximum electrical efficiency may be obtained.

tips and the armature, which may be obtained in my invention, is not possible in the constructions of the prior art for the reason that it is customary to weld, braze or solder the armature at a mid pointgto a cross, pivotal supportingmember having considerable resiliency. Experience has shown that the brazing, soldering or welding Aoperation causes afslight distortion of the parts which unbalances the armature, so that in the manufacture of the device, relatively largeair gaps must be provided to compensate for the armature distortion. AWith the increase in the dimensions of the air gap, the efficiency of the instrument as a whole is correspondingly decreased. These undesirable results are overcome in my invention bythe provision of a flat, one-piece member, wherein a pair of arms extend in opposite directions from an Y elongated armature portion and terminate in end portions adapted to be clamped between the ground surfaces of pairs offmagnetic insulating elements, the arms affording an axis about which the armaturelm move.

Another object of my invention/is to provide amagnetic unit characterized by the i fact that the windings and armature are comenclosed, thereby eliminating the of undesirable material accumulating pletely danger The minimum spacing between the polev inthe polar air gap in which the armature moves.

A further disadvantage of certain prior art devices of the character described is that it is necessary to assemble the pole pieces, the armature and the magnet successively in the highly concentrated iield between the ends of the main magnet. Under such circumstances, magnetic particles very quickly accumulate in the relatively small air gap between the pole tips and thereby lower the efficiency of theunit. In many cases, after having assembled the unit, it has been necessary to take it apart in order to remove this material. A further object of my invention, therefore, is to provide a constructionthat eliminates the above-noted diiiiculty. To this end,"l iirst assemble the armature, the coils and the associated pole pieces at a point spaced from the permanent magnet and thereafter secure the unit thus-formed to the magnet merely by bolts or the like. Thus, the parts of the unit are not dependent in any way upon the magnet' in order to secure proper ali nment. l

Other o jects and applications ofniy invention, as well as details ,of construction and operation, whereby my invention may be practiced, will be apparent more fully hereinafter, when taken in connection with the accompanying4 drawings, .wherein Fig. l is a top plan view of a translating device embodying my invention;

Fig. 2 is a transverse sectional View, the

.removed Fig. 4 is a-vertical sectional View taken ony the linea-4L of'Fig. 2; I Fig. 5 is a'perspective View of the integral one-piece die stamping which embodies the armature and .mounting means therefor;

Fig. 6 is a perspective view of the enclosed metallic unit detached`-from its permanent magnet, showing the external connections on the rear closure plate.

magnet 1 of U-shapeis provided with` aper- Referring to the drawings, a permanent f tips. Edge portions 17 and 18 of each of the 'flange portions 15, 16 are beveled and terminate in a flat edge p0rtion19 which serves as a pole end surface. The opposite pole piece y11 is similarly provided with transversely extending spaced flange ,portions or pole tips 21 and 22 which are disposed in alignment with the flange portions 15 and 16, respectively. Each of the flange portions 21 and 22 is provided with beveled edges 23 and 24 which terminate in an end surface 25 constituting a pole end surface. T hc two pole or end surfaces 19, 19 of the flanges 15 and 16 are respectively positioned in alignment with the two pole surfaces 25, 25 of the opposite flanges 21 and 22.

The pole tips 15 and 21 at least partially enclose a third side of the coil chamber 14, while the pole tips 16 and 22 at least partially enclose an opposite fourth side of the coil chamber 14. The complete closure of these sides, however, may be obtained by front and rear plates 26 and 27, respectively, the front plate 26 being of sufficient width to extend between the base portions 12 and 13 and of suflicient length to extend'from the flange portions 7 and 8 to edge portions 28 and 29 of the base portions 12 and 13, respectively. The plate 26 may besecured in this position by means of screws 31 and 32 which respectively extend into threaded apertures 33 and 34 formed in the pole tips 15 and 21. The plate 26 is of non-magnetic material so as to prevent short-circuiting of the air gap between the pole tip faces 19 and 25.

The opposite plate27 is similarly of sufficient width to extend between the base portions 12 and 13 and is of sufficient length to extend between the edge portions 28 and 29 -and the flange portions 7.* and 8.- Screws 35 and 36, which respectively extend into threaded apertures in the pole tips 16V and 22, permit the rigid mounting ofthe closure plate 27 in position. The plate 27 is made of a material which is not only non-magnetic but also an electrical insulator, such, for example,

' as bakelite, and it is provided with exteriorly accessible terminal connections 37 and 38, corresponding inner ends of which are respectively connected to two terminals of a pair of series-connected magnetizing coils 39 and 41.

In accordance with my invention, the coils 39 and 41 respectively encircle portions 42 and 43 of a flat strip-like armature member 44, the end portion 43 extending into the air gap between the pole pieces 15 and 21 and the end portion 42 extending into theopposite air gap between the pole pieces 16 and 22. The armature 44 constitutes one portion of stiff', integral, one-piece stamping, another portion of which comprisesoppositely extending arms 45 and 46, which are disposed in the plane of the strip-like armature portion 44, and elongated strip-like portions 47 and 48 which extend parallel to the armature portion 44 and are disposed in substantially the same plane therewith. The arms 45, 46 and the spaced portions 47, 48 thus constitute mounting portions for the intermediate armature portion 44.

Faces 49 and 51 of the strip-like mounting portions 47 and 48 may be caused to lie in the same plane by moving the same over aperfectly flat grinding surface, and opposite faces 52 and 53 may be similarly treated. As a result, accuracy in the parallel relationship between the faces 51, 53 and 49, 52 is assured. r`The faces 51 and 53 are positioned between accurately ground faces 54 and 55 of a pair of magnetic insulating blocks 56 and 57. The blocks 56 and 57 are respectively mountedl on inner sides of the base portions 12 and 13 of the pole pieces 7 and 8 in such v manner that sides 58 and 59 of the blocks 56 and 13 into threaded borings 63 and 64 in the blocks 56 and 57.

The strip-like mounting portion 48 may be rigidly clamped between the blocks 56 and 57 by means of a pair of through bolts 65 and 66.

The bolts 65 and 66 are respectively positioned on opposite sides of the screw members 61 and 62. The bolt 65 passes through the base portion 12, the block 56, the strip-like portion 48 and the block 57 into a threaded aperture in the base portion 13. The bolt 66, however, is oppositely directed, its threaded portion being in the base portion 12. As a result of oppositely directing the bolts 65 and 66, all the pole pieces mav be manufactured uniformly, the drilled and tapped portions of one pole piece corresponding in position with those of the others. The length of the blocks 56 and 57, as well as that of the strip-like portion 48, is such as to extend between the front and rear plates 36 and 37, whereby the complete closing of another side wall of the coil and armature chamber 14 is assured. It is noted that the elongated stamping portion 48 constitutes one portion of this side wall and that it also serves as a spacing member between the two sides of the magnetic circuit.

` gether by common means comprising a pair of oppositely directed bolts 75 and 76, as in the case of the blocks 56 and 57 and associated parts. The'through bolt 75 may be threaded in the base portion 12, while the through bolt 76 may be threaded in the base portion 17 ,so

Athat uniformity in the pole pieces 9 and 11 maybe assured.' The insulating blocks 71 and 72, and the strip-like portion 47 are of such dimensions as to serve as closure means for the remaining side of the coil and armature chamber 14.

By reason of such complete enclosure of the air gaps between the pole tips 15, 21 and 16, 22, accumulation of outside foreign maf terial in the air gaps is prevented and also the coils 39 and 4l are protected from undesirable atmospheric conditions. It Iis also noted that the flat strip-like portions 45, 47 and 46, 48 afford the armature portion 44 such mounting that the space between the pole faces 19 and 25 and the armature end portions 42 and 43 may be reduced to a minimum,-the strip-like arm portions 45 and 46 affording an axis about which the armature may move between the pairs of pole tips 15, `21and 16, 22, respectively. While not only the armature portion 44, but also the arm portions 45 and. 46 are of relatively heavy material and hence very stiff, expe- 4 rience has shown that when al powerful magnetic field is `established in the air gaps between the pole tips 15, 21 and 16, 22, the armature portion 44 may be moved as though it had a very Jflexible mounting. Since the supporting arm portions 45 and 46 are formed integral with the armature portion 44, rather than welded, brazed or soldered thereto, as in the, prior art, another cause tending to bring about a large spacing of the pole tips 15, 21 and 16, 22 is eliminated.

Still another cause making possible the close spacing of the pairs of pole tips characteristic of applicants invention is the accuracywith which the plane including the faces 54 and 67 of the blocks 56 and 71 may be spaced from the pole faces 19, 19, and the accuracy with which the faces 55 and 68 of the blocks 57 and-7 2 may be spaced from the polefaces'25. Such'accurate spacing may be accomplished byfirst mounting a pair of blocks 011 a pole piece and then accurately grinding successively the pole faces and the clamping faces of said blocks. When surfaces51, 53 and 49, 52 have been ground, so that' a parallel relation is assured; when op- ..posite faces of the strip-like armature portion 44 have been similarly ground so as to establish a parallel relation; and when the pole faces and clamping faces'` of the blocks are so ground as to lie respectively in planes having a predetermined spaced relation,it

is apparent that the spacing between the pole faces and the adjacent sides of the armature 44`may be reduced to a minimum inasmuch as the manufacturing inaccuracies of-the prior art are entirely eliminated. The eiiciency of the unit, therefore, is very high. y

The proper spacing of the coils 39 and 41 may be assured by means of wedges 77 which extend inwardly from the magnetic insul lating blocks between the coils 39 and 41'. rl'he dimensions of the wedges are such that the coil 41 is actuated into engagement with the pair of pole tips 15 and 21, while the coil 39 is actuated into engagement with the pole tips 16 and 22. Movement of the armature 44 may be imparted, for example, to a diaphragm 78, of which a portion only is shown in Fig. 1, by means of linkage 79. One end of the `lilikage 79 is secured to an extension 81 of the armature 44 which passes through a relative- A. ly small aperture 82 in the front closurev `plate 26,

Should it be desirable to repair or replace any of the movable parts contained within the chamber 14, it is only necessary to remove the clamping bolts 5 and 6 and thereafter remove the pole pieces 9 and 11 and intercounected parts to a point spaced from the per'- i'nanent magnet 1. An advantage of such arrangement is that it is not necessary to make the adjustments or repairs in the heavy magnetic field that extends between the ends 3 and 4 of thelpermanent magnet 1.

It is apparent, therefore, that the translating device embodying my invention is characterized, among other things, by the employment of an integral one-piece stamping having portions adapted to serve as armature and mounting portions; by elimination of springs; by the enclosure of the working parts, as well as the air gap, in a chamber, so that undesirable foreign material is prevented from decreasing the efficiency of operation; by the close adjustment in the air gap and the reduction to a minimum in the spacing between the armature and the pole tips; and by the fact that theseveral parts are suit-able for inexpensive quantity production methods of manufacture, said paits being readily assembled with a minimum expenditure of time and'of money.

l/Vhile I have shown only one embodiment of my invention, for the purpose of describing the same and illustrating its principles of construction and operation, it is apparent that various changes and modifications may be made therein, without departing from the spirit of my invention and I desire, therefore.

that only such limitations shall -be imposed thereon as are indicated in the appended claims or as are demanded by the prior art.

I claim:

l. In apparatus of the character described, a iat metallic stamping comprising a pair of spaced portions adapted to co-act with securing means, an intermediate portion constituting an armature, and portions respectively extending between said intermediate portion and said pair of portions affording said intermediate portion an axis about which movement may occur.

2. In apparatus of the character described, a pair of spaced strip-like portions adapted to be secured to clamping means, an intermediate strip-like portion constituting an armature, and portions extending between said intermediate portion and said spaced portions atl'ording said armature an axis' about which movement may occur.

3. Magnetic apparatus comprising meansv for forming a plurality of poles, an integral one-piece member comprising a pair of spaced parallel portions, an intermediate portion constituting an armature and interconnecting portions between said spaced parallel portions and said yintermediate portion, and means co-acting with said spaced parallel portions for positioning said armature portion in desired relation to said poles.

4. The combination with a pair of members provided with pole tips, of a member having integral armature and mountingV portions, Y a plurality of insulating elements mounted on oppositesides of said mounting' portion, and means whereby said mounting portion may be clamped between said elements and `said pair of members, saidmounting portion including an arm portion permitting a movement of said armature portion relative to said poles.

5. Apparatus of the character described comprising a pair of members provided with pole tips, a member having integral armature and mounting portions, said mounting portions comprising a pair of arms affording an axis about which said armature portion may move and end portions, a plurality of blocks mounted on opposite sides of said end portions. and means whereby said end portions, said blocks and saidpair of members may be clamped together.

6( A pair of members provided with pole tips, a member including integral armature' and mounting portions, said mounting portions including arm portions respectively eX- tending in opposite directions from said armature portion and end portions, pairs ot blocks disposed on opposite sides ot' said end portions, and means whereby said end portions mayY be clamped between said blocks and said pair of members. i

7. Apparatus of the character described comprising a pair of spaced strip-like portions, an intermediate strip-like portion, in-

terconnecting arm portions,vpairs of blocks positioned o n opposite sides of said spaced strip-like portions, pairs of members having polesLand means whereby said intermediate strip-like portion may be disposed in desired relation to said poles, said means serving to clampvtogether said pairs of members, said pairs of blocks and said pairs of spaced strip like portions.

8. The combination with a fiat metallic member comprising a plurality of spaced portions, an intermediate portion and inter-- connecting arm portions, of pairs of blocks having ground surfaces positioned in abutting relation to said spaced portions, pairs ot rmembers having pole tips, and means whereby said spaced portions may be clamped between the ground surfaces of said blocks with said intermediate portion in desired spaced relation to said poles.

9. An enclosed magnetic unit comprising a pair of spaced pole pieces constituting two ot the sides of a chamber, closure plates extending between said pole pieces and constituting two more sides of said chamber, and magnetic insulating members so positioned as to at least substantially close the remaining sides of said chamber.

l0. A unit comprising a pair of spaced pole pieces constituting two of the sides of a coil chamber, closure plates extending between said pole pieces and constituting two more sides of said chamber, magnetic insulating members so positioned as to at least substantially close the 'remaining sides of said chamber, andI a member positioned in said coil chamber comprising an armature portion .and a mounting portion, said mounting portion being positioned between said insulating members. I

11. A pair of pole pieces having base portions constituting two of the sides of a chamber and transversely extending pole-tip portions constituting at least portions of two other sides of said chamber, magnetic insulating elements positioned to constitute at least a. portion of the remaining two sides of said chamber, and amember having an armature portion disposed in said chamberI and vother portions respectively positioned between said magnetic insulating elements.

l2. A pair of pole pieces having base portions constituting two of the sides of a chamber and transversely extending pole-tip portions disposed in two other sides of said chamber, magnetic insulating elements positioned to constitute at least a portion of the remaining two sidesof said chamber. a member havf ing an armature portion disposed in said chamber and other portions respectively positioned between said magnetic insulating elements, and closure plates for said secondmentioned sides of the chamber.

13. Electro magnetic apparatus of the character described comprising a pair ot` pole pieces having base portions adapted to constitute two sides of a chamber and transversely extending pole-tip portions, and clo'- sure plates for another pair of sides of said chamber mounted on said pole-tips.

14. An electro-magnetic unit comprising a pole piece having a base portion and a pair of transversely extending spaced' pole-tip portions, a member comprising an armature portion and a mounting portion, means whereby said mounting portion may be insulatingly mounted on said base portion, an actuating winding surrounding said armature, and means whereby said winding may be wedged between said pole-tip portions.

l5. An electro-magnetic device comprising a pole piece having a base portion and transversely extending pole-tip portions, a inember comprising an armature portion and a mounting portion, said mounting portion having an arm and an end port-ion, said arm portion aii'ording an axis about which said armature portion may move, an insulating element carried by said base portion affording said mounting portion a support, a pair of coils encircling said armature and respectively disposed on opposite sides of Said arm, and means whereby said coils may be wedged intermediate said pole-tip portions.

3o JOHN S. TIMMONS. 

